A stunning exhibition quality perforation shift error. Unmounted mint cylinder block of eight. Each stamp with huge shift of vertical perforations resulting in Queen's head and value appearing centrally rather than in top left and bottom right corners. Each stamp also has BROAD CENTRAL PHOSPHOR BAND instead of normal two side bands. Four smaller "stamps" at left of block without value and incorporating date, cylinder number and printers logo into design. Possibly a unique positional piece of this error. A light gum wrinkle in lower left margin.